Quadratic Equations
Quadratic Inequalities
JEE Main 2021
Grade 11

Question:

The number of integral values of $k$ for which the equation $x^2 - 2(3k - 1)x + 8k^2 - 7 > 0$ holds for all real $x$ is:
(1) $0$
(2) $1$
(3) $2$
(4) $3$

Step-by-Step Solution

Key Concept: For the quadratic (leading coeff. positive) to be always positive, the discriminant must be $< 0$. Compute $D < 0$ to get a quadratic inequality in $k$, then count integers inside that range.
The detailed step-by-step mathematical proof is available inside the Mathbee app workspace.
Correct Answer: (2)

Master Quadratic Equations with Mathbee

Practice this topic under real exam conditions with strict timers, or ask our AI Mentor to explain the concepts step-by-step.

Start Practicing for Free